Knife for rotary trimmers



(No Model.) I A. S. VOSE. KNIFE FOR ROTARYTRIMMERS. No. 546,750 Patented Sept. 24, 1895.

FIE-E- ANDREVI B.GRAMM PHOTO-LTI'HQWASHINGWKRC.

' FFEC AMBROSE S. VOSE, OF BOSTON, MASSACHUSETTS.

KNIFE FOR ROTARY I'RIMMERS.

SPECIFICATION forming part of Letters Patent No. 546,750, dated. September 24, 1895.

Application filed January 2,1895. Serial No. 533,525. (No model.)

To all whom it may concern:

Be it known that I, AMBROSE S. VOsE, of Boston, in the county of Suffolk, State of Massachusetts, have invented certain new and useful Improvements in Knives for R0- tary Trimmers, of which the following is a description sufficiently full, clear, and exact to enable any person skilled in the art or science to which said invention appertains to make and use the same, reference being had to the accompanying drawings, forming part of this specification, in which-- Figure 1. is a perspective View of my improved trimming-knife; Fig. 2, an end elevation of the same shown in engagement with an emerywheel, which is represented in dotted lines; and Fig. 3, a face elevation of the knife.

Like letters of reference indicate corresponding parts in the different figures of the drawings.

Much difficulty is experienced in grinding knives of this class, which is provided with a beveled chiseled edge, from the fact that the corner or edge of the emery-wheel rapidly becomes worn away or rounded, which causes the operator to tilt the knife slightly. This, in grinding the fiat face of the knife, which is preferable in nearly all cases to grinding the beveled edge, results in rounding or chamfering the cutting-edge in such manner that when the knife is used in a rotary-wheel for trimming shoe-sole edges or similar articles, a scraping rather than a cutting move ment is imparted. The knife is ground on its flat surface by engaging it with the side of an emery-wheel. This class of knives is used for a great many purposes other than that of sole-trimming, but the same result is effected.

My improvement is designed particularly to overcome this objection and to produce a blade which in addition to afiording all of the results necessary to the proper working of blades of this class will last longer and can be ground on their flat or side surfaces without turning the edge and without injuring the corner or edge of the emery-wheel, which naturally results in inconvenience to the operator in holding the knife in such a plane that its cuttingedge will not be mal formed.

In the drawings, A represents the knife considered as a whole, which is of a WGHkHOWII shape adapted to be secured in a rotary trimming-wheel in a line parallel to a tangent of said wheel. This knife has a beveled or chiseled surface '0 ending in the cutting-edge f in the usual manner, and a flat side or surface 25. Laterally in said flat side or surface and pitched into a plane parallel with the beveled surface 1), a groove h is formed above the pin or attaching opening 10 of said blade. The upper wall on of said groove is in parallelism with the bevel o of said blade. In use, in grinding the knife it is far preferable to engage the face 15 with the emery-wheel B on its sidein preference to its periphery w, as shown in Fig. 2. Ordinarily, were the blade solid the edge w of the wheel would be rapidly worn away. In the form of knife that I describe, however, said edge, while the knife is being ground, registers with the opening or groove h, as shown in Figs. 2 and 3, where it is not in contact with any of the metal. The surface t above said opening can thus be ground so that the cutting-edge f is perfect, as said surface will at all times be formed vertically and said edge, even by the exercise of ordinary care, will not be chamfered toward the beveled surface.

It will be understood that I do not confine myself to forming a trimming-knife in this manner, but the device is adapted for use with chisels or any form of knife having a more or less beveled edge wherein it is always preferable to grind the flat rather than the beveled surface. Moreover, the sole purpose for inclining the groove 71. into parallelism with the beveled edge, is that more material is left for use or for wearing away than would result were the groove formed horizontally, as the figures are represented.

Having thus explained my invention, what I claim is- 1. As a new article of manufacture a knife having a chisel edge and provided with a transverse groove extending across its fiat face below said edge, substantially as and for the purpose set forth.

2. As a new article of manufacture aknife having a chisel edge and provided with a transverse groove extending completely across its flat face; said groove being ap proximately in parallelism with said edge.

AMBROSE S. VOSE.

Witnesses:

K. DURFEE, O. M. SHAW. 

